Targeted Muscle Reinnervation

Johns Hopkins Medicine and APL are collaborating on the use of the Modular Prosthetic Limb (MPL) and targeted muscle reinnervation (TMR) surgery.

TMR is a new surgical procedure that reassigns nerves that once controlled the arm and the hand. By reassigning existing nerves, doctors can make it possible for people who have had upper-arm amputations to control their prosthetic devices by merely thinking about the action they want to perform. Once experimental, this innovative procedure is now available at The Johns Hopkins Hospital. People who undergo the targeted reinnvervation surgery will be fitted with and trained to use a myoelectric prosthetic arm.

APL is collaborating with the Department of Surgery at Johns Hopkins Medicine on clinical trials using the MPL for patients who have received TMR surgery.

Who Might Benefit from TMR Surgery?

Those interested in the procedure to better control their prosthetic arm must undergo a medical review to determine their eligibility. In general, patients must meet the following criteria:

Amputation above the elbow or at the shoulder within the last 10 years

Stable soft tissues

Willingness to participate in rehabilitation

Those who were born without part or all of their arm and those who have nerve damage, degeneration, or paralysis are not candidates for this procedure.

TMR is a specialized surgical procedure developed by the expert staff at Johns Hopkins Medicine, including Albert Chi, M.D., the Medical Director for the Targeted Muscle Reinnervation Program. Dr. Chi also serves Assistant Professor of Surgery at Johns Hopkins Medicine. He is a trauma surgeon whose practice includes critical care, trauma, and acute care surgery. He has a background in biomedical engineering, and his clinical research is focused on improving the lives of individuals with traumatic injuries, with an emphasis on motor control. Dr. Chi is also commissioned as a lieutenant commander in the U.S. Navy Reserve and is dedicated to serving our country and helping care for the wounded warriors returning home and those injured in the field.

The Applied Physics Laboratory, a not-for-profit division of The Johns Hopkins University, meets critical national challenges through the innovative application of science and technology.
For more information, visit www.jhuapl.edu.